AMD Ryzen 7 1700 Undervolting, How Low Can You Go?

I finally got my hands on AMD Ryzen 7 1700. This is a nice and cheap Octa-Core Processor running at 3.2 GHz on all cores with precision boost enabled. This processor isn’t going to beat Intel Core i7 6900K, but it is still a very fast processor. Gaming performance might seem disappointing for some people, but I am not going to talk about that. Mainly because I am still using a soon to be 4-year-old AMD Radeon R9 290. So, Ryzen 7 1700 will not likely become a bottleneck in gaming with this old Graphics Card.

I am not going to do any benchmark test here, I am just testing the processor power consumption and see how far low I can take it when undervolted. I will measure the power consumption on 3 states : Idle, Load CPU-Z Stress Test, and Load Handbrake Test.

Since Radeon R9 290 idle power consumption is rather inconsistent, I put out the card and switch it with Geforce GT 710 which turns out to much more consistent in power consumption.

So, I lowered to VCore on ASRock UEFI by 0.1 V which means the target VCore is 1.0875 V instead of the default 1.1875 V . I can lower it a little bit more to 1.075 V but that’s unlikely to make drastic changes. Anyway here is the result.

Idle Power Consumption / Temperature

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Reducing the voltage by 0.1V also reduce the power consumption by 5 Watts. This is a good thing but I am still saying this disappointing. Why? Because my 5-year-old Ivy Bridge system can draw just a bit higher than 40 Watts with the same setup when undervolted by 0.08V.

Temperature is excellent I think although undervolting only brings down the temperature by 0.5 °C. My room temperature is around 27 °C. So, 29.5 C means the temperature is just 2.5 °C above my room temperature. Nothing to concern here, thanks to my 8-year-old OCZ Vendetta 2. Anyway, using Radeon R9 290 will make the idle temperature hovers around 32 – 35 °C. It seems the Graphics Card also adds some heat to the processor.

Load CPU-Z Stress Test Power Consumption / Temperature

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In this test, power consumption only lowers by 5 watts from 115 Watts to 110 Watts. Maybe because Ryzen 7 1700 is already very efficient so there isn’t much room to reduce to power consumption while keeping the clock speed at 3.2 GHz. Anyway, 110 Watts is a great number though. This is an 8-Core processor running at full speed with full load after all!

Temperature reduction from undervolting is only 1.2 °C. Nothing significant here. Both are still below 50 °C which is fantastic. Using Radeon R9 290 will the temperature hovers around 47-48 °C though. Still under 50 °C which is far from concerning.

Load Handbrake Power Consumption / Temperature

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I choose Handbrake to represent real world power consumption. Handbrake is a video encoding software and this software utilizes every threads and put a great balanced load across every thread. As you can see from the graph, power consumption during Handbrake video encoding is actually higher than during CPU-Z stress test. Undervolting only brings down the power consumption by merely 6 watts though. However, 134 Watts during video workload is amazing for an 8-core processor. My 5-year-old Core i5-3570K consumes about 120 Watts. While it sounds more efficient, it actually isn’t because Ryzen 7 1700 can finished the task twice faster than Core i5-3570K. Overclock the Core i5-3570K to 4.5 GHz will make the CPU draws more than 150 Watts. Pretty much less efficient than Ryzen 7 1700. For another comparison, Core i7-2600K also draws around 150 Watts during video encoding when not overclocked but it takes close to twice longer than Ryzen 7 1700 to finish the task.

Temperature only lowers by 1 °C again during Handbrake. Not much improvement here, especially with the temperature is still lower than 50 °C which isn’t concerning at all. Oh yeah, switching Gefore GT 710 with Radeon R9 290 will increase the temperature to 52.5 °C. A bit higher but also still not concerning.

Conclusion
AMD Ryzen 7 1700 is designed to be an efficient processor. So, undervolting doesn’t do much in reducing the power consumption or lowering the temperature. Instead of undervolting, people will likely to overclock this processor to go beyond Ryzen 7 1800X clock speed.

There is one thing that AMD will need to take a note here. The idle power consumption is disappointing. It’s about 10 Watts higher than 5-year-old Ivy Bridge. While this is acceptable on Desktop PC, the story on notebook side is pretty much different. 10 Watts on mobile device is huge. AMD will have to put some magic on Raven Ridge to make sure the APU won’t draw too much power on idle state, hopefully without sacrificing performance by any means.